Force generation in glycerinated insect-flight muscles without ATP

Zusammenfassung Durch Zugabe und durch Auswaschen von Mg-Pyrophosphat (0,5 mM) oder Mg-Tripoly-Phosphat (1 mM) konnten (in Abwesenheit von ATP) in glyzerinextrahierten Fasern von fibrillären Insektenmuskeln (Lethocerus maximus) reversible Kontraktionszyklen und Änderungen des Dehnungswiderstandes bewirkt werden.

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Supported by Grant No. Ru 154/b of the Deutsche Forschungsgemeinschaft. The excellent technical assistance of Mrs.Helgard Jung is gratefully acknowledged.     

Hendrik Antoon Lorentz und Emil Wiechert

Ohne Zusammenfassung Vorgelegt von S. Flügge     

Studies on the modulation of the desensitization of the pituitary gland by luteinizing hormone-releasing hormone in the ovariectomized rat

In ovariectomized rats the desensitization of the LH cells in vivo, which develops during constant rate infusion of LHRH, 1) does not depend on a concomitant depletion of the pituitary LH stores, 2) proceeds normally when the hypothalamo-pituitary connection has been severed and 3) is a process in which LH itself is not involved.     

Immunofluorescent localization of the types of collagen synthesized in the embryonic mouse tooth germ]

The different types of collagen synthesized by embryonic Mouse tooth germs were analysed using an immunohistiological method. The tooth germs were shown to synthesize at least three genetically distinct collagen types: I, III and IV.     

Recognition sequence of bacteriophage phi X174 gene A protein--an initiator of DNA replication

Gene A protein, the initiator protein of bacteriophage phi X174 DNA replication, cleaves synthetic single-stranded oligodeoxyribonucleotides at the same site as the corresponding sequence at the phi X origin. The results identify the recognition sequence within the decamer CAACTTGATA which is cleaved next to the G residue. Further requirements for cleavage of double-stranded DNA by the gene A protein are supercoiling and an A + T-rich domain adjacent to the recognition sequence.     

Cloning of the mycobacterial epitope recognized by T lymphocytes in adjuvant arthritis

Adjuvant arthritis (AA) is a chronic disease inducible in rats by immunization with an antigen of Mycobacterium tuberculosis. After the isolation of arthritogenic T-cell lines and clones, it became possible to demonstrate that the critical M. tuberculosis antigen contained an epitope cross-reactive with a self-antigen in joint cartilage. Like AA rats, patients suffering from rheumatoid arthritis demonstrated specific T-lymphocyte reactivity to the M. tuberculosis fraction containing the cross-reactive epitope. To characterize the critical M. tuberculosis epitope we used AA T-cell clones to screen mycobacterial antigens expressed in Escherichia coli and genetically engineered truncated proteins and synthetic peptides. The AA T-cell clones recognized an epitope formed by the amino acids at positions 180-188 in the sequence of a Mycobacterium bovis BCG antigen. Administration of this antigen to rats induced resistance to subsequent attempts to produce AA.